Abstract:A novel hydrometallurgical process of copper recovery from waste printed circuit boards was introduced. In this process, air was blown into solution as oxidant for copper leaching in NH3-(NH4)2SO4-H2O system, while leaching residue was treated by physical method. The effects of ammonia and ammonium sulfate concentration, ratio of solid to liquid, leaching temperature, air flow and leaching time on copper leaching rate were investigated. The results show that copper leaching rate is up to 96.67% under the following optimum conditions including ammonia concentration of 2 mol/L, ammonium sulfate concentration of 2 mol/L, ratio of solid to liquid of 1∶20, leaching temperature of 25 ℃, air flow of 8 m3/h and leaching time of 4 h.